Collision-Resistant usage of MD5 and SHA-1 via message preprocessing

摘要: A series of recent papers have demonstrated collision attacks on popularly used hash functions, including the widely deployed MD5 and SHA-1 algorithm. To assess this threat, natural response has been to evaluate extent which various protocols actually depend resistance for their security, potentially schedule an upgrade a stronger function. Other options involve altering protocol in some way. This work suggests different option. We present several simple message pre-processing techniques show how can be combined with or so that applications are no longer vulnerable known attacks. For applications, may viable alternative upgrading